LG 55 B4 vs TCL C75B

The brightness results in HDR materials LG B4 are very good. It is true that none of them exceed 1000 nits, although the luminance stability is excellent and looks practically the same in every scenario. The only moment where the tested television performs worse is the last scene, although this should not come as a surprise. Large frames filled with a lot of white have always been, and will likely continue to be, somewhat of a weakness for OLED televisions. However, the combination of perfect contrast, black levels, and brightness in the LG B4 allows for a full spectrum of the HDR effect. Additionally, the incredibly high coverage of the DCI-P3 colour gamut, which reached 99%, deserves recognition. As a result, colours look incredibly vibrant and stunning.

During our brightness test, the TCL C75B "spat out" around 380 nits of brightness. We recorded similar results while watching most of the films we tested. These can be considered average – the TV performs decently in this segment, but around 400 nits is definitely too low to fully experience the magic of HDR effects. Of course, such results are better than those of budget models, which can achieve nearly half the brightness values. However, for HDR enthusiasts seeking stronger lighting effects and greater realism, the C75B may prove insufficient. On the plus side, it's worth mentioning the coverage of the DCI-P3 colour gamut at 95%. This is a very good result that easily suffices to enjoy a wide range of colours in content available on popular streaming platforms. Vivid and rich colours are definitely a strong point of this model.

The best factory mode prepared by the manufacturer is "Filmmaker," and we used it throughout the entire testing procedure. We must admit that the unit we received straight out of the box had quite decent colour reproduction. The biggest issue in both SDR and HDR content turned out to be white balance. In the former, there was a strong dominance of red, resulting in a noticeable yellow tint in the displayed image, particularly evident on skin tones and whites. In high-quality materials, this colour was also pronounced, but due to a lack of blue, there were also signs of green visible. Besides these shortcomings, we also encountered issues with greyscale and the colours themselves.

TCL C75B offers various picture modes, but in our opinion, the best choice is the “Film” mode. Although its settings are quite decent, the TV struggles with certain colour reproduction issues. In tests, we noticed that the image had a noticeably pinkish hue compared to what could be considered correct. This effect was particularly evident in skin tones, which appeared unnaturally flushed. The main culprit of this phenomenon turned out to be the white balance, characterised by an excess of blue and red in both HD and 4K HDR materials.

An additional problem was the way brightness was reproduced. The gamma, which is responsible for the visibility of details in darker materials, was definitely boosted, causing details in the darkest parts of the screen to be invisible, disappearing into complete black (e.g., the bottom part of the screen in the comparison image - the area around the actress's ear). The situation was similar on the EOTF curve, which was below the correct value, suggesting that a similar issue may be encountered in 4K HDR content.

Thanks to our experience and the appropriate tools, we decided to take matters into our own hands and check how much could be extracted from this model after professional calibration. The details are described in the next section.

LG B4 has been providing very advanced calibration tools in its TVs for years. We can even say that as the only manufacturer on the market, it allows for such deep intervention in image adjustment. Thanks to these, we were able to calibrate the device so well. The evidence of this is the extremely low deltaE errors, which can be said to stand at a reference level. Both SDR and HDR materials now look exactly as the film director intended. It is no coincidence that TVs of this brand are most often used as preview screens for various graphic or post-production studios.

After calibration, TCL C75B has clearly improved when it comes to colour reproduction. Although the TV doesn't offer too many options for adjusting the white balance, we managed to improve its settings quite a bit. As a result, the image is no longer overly pink, and the colours now look much more natural and harmonious.

The gamma jump that was previously an issue hasn't completely disappeared, but we were able to significantly reduce it. This has made details in dark scenes more visible – both in HD and 4K HDR content.

Unfortunately, the lack of local dimming is still noticeable. The 'blooming black' effect remains, but that's a limitation of the display itself. Still, the colours post-calibration look significantly better, and the image is much more pleasant to watch.

In this paragraph, we will take another look at the tonal transition smoothing feature, but we will also check how the TV handles lower quality material. As we have managed to check, the setting responsible for smooth gradation works quite effectively, although it has its weaker moments. While the feature works well with SDR content, it becomes less useful with HDR content. Even at the lowest of options, it blurs essential details, so we advise against using it.

The image scaling on LG B4 is rated fairly moderately positively. Although there is no edge splitting, the image itself is naturally "soft". We can change this by adjusting the sharpness slider.

TCL C75B has a feature for smoothing tonal transitions, but unfortunately, we cannot praise it. Regardless of the selected level – low or high – tonal transitions in older materials remained visible, as if the feature wasn’t working at all. It’s hard to say anything positive about it, as in practice it seems completely useless.

Image scaling is better. The TV handles it quite decently, although on thinner elements, like branches in the background, you can see slight jaggedness. However, this is not something that significantly hinders everyday viewing.

Unfortunately, a bigger problem turned out to be overscan, or cropping of the image edges. In our tests, it happened that news ticker or other elements close to the edge of the screen were cut off. This is definitely something to pay attention to, especially if we use the TV for watching news programs or content with text on the screen.

The maximum refresh rate we can set on the LG B4 is 120 Hz. This is the absolute minimum for those who require high image smoothness. The manufacturer has implemented a multi-level motion smoother called "TruMotion". It has been divided into two separate sliders that adjust the sharpness of moving images (De-Blur) and stuttering (De-Judder). Both sliders can be set in the range from 0 to 10, with each level affecting the degree of smoothness, so everyone can find their sweet spot.

The LG OLED B4 panel features an average response time of 0.1 ms (which directly results from our measurements), allowing for an incredibly clear image, unattainable for LCD TVs, which have response times of even several milliseconds. This can be clearly seen in images from the "UFO Test", showing no trace of blur trailing behind the object.

TCL C75B definitely has something to offer gamers. The television is equipped with a panel that can display images with a refresh rate of 144 Hz in 4K, and even 240 Hz in Full HD. These are really impressive results, especially for a model from the budget range.

On top of that, there are features for improving smoothness and reducing motion blur in films. The "Motion" option allows for precise adjustment of the effect on a 10-point scale, providing significant personalisation possibilities – everyone can set the smoothness to their liking.

The LG B4 television is equipped with four full-fledged HDMI 2.1 ports with a full bandwidth of 48Gbps. All functions corresponding to this standard activated without any issues, and throughout the entire testing procedure, they caused no problems. The combination of such extensive functionality and low input lags leads us to say that the tested television is truly designed for gaming. This is not surprising, considering that the manufacturer has always placed great emphasis on this. Therefore, we can enjoy both a properly implemented HGIG mode and gameplay in Dolby Vision with low latency. Such a tandem will surely attract the attention of all passionate gamers for whom quality is the most important.

A standard feature in televisions from the Korean manufacturer is also the implementation of GameBar, allowing for quick adjustments of settings "on the fly," without the need to exit the game. It also enables image adjustments for individuals with visual impairments, which is an extremely nice touch. Another important piece of information is that when the VRR technology is turned on, we will not experience a drop in contrast. This is, of course, due to the construction of the panel and the lack of conventional backlighting. However, it is normal for shades of grey to flicker slightly, although this is a characteristic feature of this function regardless of the manufacturer and the television.

In summary: The LG B4, like all OLEDs from the manufacturer equipped with 120Hz panels and HDMI 2.1 ports, creates a harmonious whole with the console. In practice, it is a complete television, and if we expect the highest possible efficiency in gaming, the B4 will be the ideal choice.

TCL C75B is undoubtedly a television designed with gamers in mind. It has almost everything needed for even the most demanding console users. With the implementation of full bandwidth HDMI 2.1, the TV supports features like ALLM (automatic low latency mode) and VRR (variable refresh rate) – operating within the full capabilities of the TV, up to 240 Hz in Full HD resolution.

Additionally, the television supports advanced HDR technologies, including Dolby Vision and HGiG, which allows for even better detailing in HDR-optimised games. C75B is also equipped with a very convenient interface for gamers in the form of Game Bar, where you can check all key parameters such as refresh rate, input lag, or picture settings – all just a click away.

In one sentence: C75B is a great choice for gamers, offering a wide range of features that fully enable enjoyment of the capabilities of modern consoles and games.